<div>
  <style>
    p.upgrading{
        color: #3344bb;
        font-size: 20px;
    }
    img.upgrading_img{
        margin: auto;
    }
  </style>
  <p class="upgrading">OSSEAN is upgrading, It should takes about 1 hour, Please View Later 。。。</p>
  <p>
    <%= image_tag 'upgrading.jpg', :class =>'upgrading_img', :size => '900x900' %>
  </p>
</div>